Facebook-owned WhatsApp continues to climb in monthly usage. CEO Jan Koum revealed on his Facebook page that the popular messaging company now has over 800 million active monthly users, which is an increase of 100 million since January. At this rate, WhatsApp will reach the one billion user milestone before the end of 2015.

WhatsApp recently went beyond texting, activating voice calling for Android users. This feature will soon be available to iOS users, and according to a leaked screenshot could arrive on Windows Phone soon, too.

Facebook purchased WhatsApp for $19 billion in 2014.